Trypanosoma cruziPromotes Transcriptomic Remodeling of the JAK/STAT Signaling and Cell Cycle Pathways in Myoblasts
FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY
Authors: Nisimura, Lindice M.; Coelho, Laura L.; de Melo, Tatiana G.; Vieira, Paloma de Carvalho; Victorino, Pedro H.; Garzoni, Luciana R.; Spray, David C.; Iacobas, Dumitru A.; Iacobas, Sanda; Tanowitz, Herbert B.; Adesse, Daniel
Abstract
Chagas disease is responsible for more than 10,000 deaths per year and about 6 to 7 million infected people worldwide. In its chronic stage, patients can develop mega-colon, mega-esophagus, and cardiomyopathy. Differences in clinical outcomes may be determined, in part, by the genetic background of the parasite that causes Chagas disease.Trypanosoma cruzihas a high genetic diversity, and each group of strains may elicit specific pathological responses in the host. Conflicting results have been reported in studies using various combinations of mammalian host-T. cruzistrains. We previously profiled the transcriptomic signatures resulting from infection of L6E9 rat myoblasts with four reference strains ofT. cruzi(Brazil, CL, Y, and Tulahuen). The four strains induced similar overall gene expression alterations in the myoblasts, although only 21 genes were equally affected by all strains.Cardiotrophin-like cytokine factor 1(Clcf1) was one of the genes found to be consistently upregulated by the infection with all four strains ofT. cruzi. This cytokine is a member of the interleukin-6 family that binds to glycoprotein 130 receptor and activates the JAK/STAT signaling pathway, which may lead to muscle cell hypertrophy. Another commonly upregulated gene was tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein theta (Ywhaq, 14-3-3 protein Theta), present in the Cell Cycle Pathway. In the present work, we reanalyzed our previous microarray dataset, aiming at understanding in more details the transcriptomic impact that each strain has on JAK/STAT signaling and Cell Cycle pathways. Using Pearson correlation analysis between the expression levels of gene pairs in biological replicas from each pathway, we determined the coordination between such pairs in each experimental condition and the predicted protein interactions between the significantly altered genes by each strain. We found that although these highlighted genes were similarly affected by all four strains, the downstream genes or their interaction partners were not necessarily equally affected, thus reinforcing the idea of the role of parasite background on host cell transcriptome. These new analyses provide further evidence to the mechanistic understanding of how distinctT. cruzistrains lead to diverse remodeling of host cell transcriptome.
Decreased secretion and profibrotic activity of tubular exosomes in diabetic kidney disease
AMERICAN JOURNAL OF PHYSIOLOGY-RENAL PHYSIOLOGY
Authors: Wen, Jin; Ma, Zhengwei; Livingston, N. J.; Zhang, Wei; Yuan, Yanggang; Guo, Chunyuan; Liu, Yutao; Fu, Ping; Dong, Zheng
Abstract
Tubular changes contribute to the development of renal pathologies in diabetic kidney disease (DKD), including interstitial fibrosis. It is unclear how tubular cells relay signals to interstitial fibroblasts. Recently. exosomes have been recognized as crucial mediators of intercellular communication. We hypothesized that exosomes secreted from tubular cells may stimulate fibroblasts for interstitial fibrosis in DKD. In this study, we isolated and purified exosomes from the renal cortex of DKD mice and high glucose-treated mouse proximal tubular cells. Compared with nondiabetic mice, exosome secretion in kidney tissues decreased in DKD mice. Likewise, high glucose incubation reduced exosome secretion in mouse kidney proximal tubular BUMPT cells. To study the effect of tubular cell exosomes on fibroblasts, exosomes from BUMPT cells were added to renal fibroblast NRK-49F cell cultures. Notably, exosomes from high glucose conditioned BUMPT cells induced higher proliferation. significant morphological change, and substantial production of fibronectin, alpha-smooth muscle actin, and collagen type I in NRK-49F fibroblasts. Proteomics analysis was further performed to profile the proteins within tubular cell exosomes. Interestingly, 22 proteins were found to be differentially expressed between tubular exosomes derived from high glucose conditioned cells and those from normal glucose conditioned cells. Cytoscape analysis suggested the existence of two protein-protein interaction networks in these exosomal differentially expressed proteins. While one of the proteinprotein interaction networks comprised enolase 1 (Eno1), heat shock protein family A member 8 (Hspa8). thioredoxin 1 (Txn1), peptidylprolyl isomerase A (Ppia), phosphoglycerate kinase 1 (Pgk1), DNA topoisomerase II-beta (Top2b), and beta-actin (Actb), the other had the family proteins of human leucocyte antigen F (Ywhag), a component of the ND10 nuclear body (Ywhae), interferon regulatory factor-8 (Ywhaq), and human leucocyte antigen A (Ywhaz). Gene expression analysis via Nephroseq showed a correlation of Eno1 expression with DKD clinical manifestation. In conclusion, DKD is associated with a decrease in exosome secretion in renal tubular cells. Exosomes from high glucose conditioned tubular cells may regulate the proliferation and activation of fibroblasts, contributing to the paracrine signaling mechanism responsible for the pathological onset of renal interstitial fibrosis in DKD.